Suspension Travel Control System

ABSTRACT

A suspension travel control system for a vehicle suspension is disclosed. The suspension travel control system includes a stop post secured to the vehicle frame and a suspension travel control formation that includes a base and a body. The stop post is positioned in a space defined by the body. The suspension travel control formation may be secured to the axle, the main support member or incorporated into the axle coupling assembly to provide a rebound and jounce stop as well as longitudinal redundancy in the event of the failure or loss of a longitudinal linkage.

BACKGROUND OF THE INVENTION Field of the Disclosure

The invention relates to heavy-duty axle/suspension systems and specifically to suspension travel control systems. More particularly, the present disclosure is directed to a suspension travel control systems for heavy-duty axle/suspension systems which is low cost, easy to manufacture, customizable and available for use in original equipment design and manufacturing as well as aftermarket and retrofit applications, thus making it useful on a variety of axle/suspension systems, and further, which eliminates or reduces the need for other suspension components that control or limit suspension travel, thus reducing the unsprung weight of the suspension system.

A heavy-duty vehicle such as a vehicle cab, semi-trailer or trailer typically is equipped with at least one and usually more than one axle/suspension system. The axle/suspension systems are suspended from the vehicle frame and will typically include an axle connected or secured to a suspension linkage which positions and restrains movement of the axle in a longitudinal and/or vertical direction, such as for example, a leaf spring; a leading arm or trailing arm in the form of rigid beam or beam spring or main support member; or a control arm. The suspension linkage is movably connected to the vehicle frame, such as for example, when one end of the linkage is pivotally connected to the vehicle frame with the use of a bushing, pivot bolt and bracket. In this example, another end of the linkage is typically attached to the vehicle frame via an air spring. A shock absorber may also be attached to and extend between the linkage and the vehicle frame.

During normal operation of the vehicle, the wheels attached to the axle encounter bumps and depressions in the road over which the vehicle is traveling forcing the linkage and the axle to move up and down, or in the particular example referred to above pivot about an axis of rotation defining an arc of travel. Various components of the axle/suspension system, and in particular the linkage bushing assemblies, the air springs and the shock absorbers, all cooperate in reacting the loads encountered by the vehicle wheels. The suspension system serves to cushion the vehicle frame and ultimately minimizes undue wear and damage to the frame and any cargo being transported, and also makes the ride comfortable for passengers.

During maximum downward travel or full rebound of the suspension system, a positive rebound stop is required to prevent damage that would otherwise occur to suspension componentry, such as the air springs (if present), and in severe cases, to the linkage and other suspension components. Shock absorbers can provide this positive stop during suspension rebound. They also function as hydraulic dampers for the air springs. However, reliance on a shock absorber to fulfill the rebound stop requirement significantly shortens the life of the shock absorber. Moreover, the cost and weight of alternative rebound stop technologies, such as those that use chains and the like, are not insubstantial and approach that of hydraulic shock absorbers.

Improvements in air spring technologies eliminate the reliance on hydraulic dampers. However, the full benefit and advantages of these technologies, including but not limited to the potential for reducing the overall cost and weight of suspension systems in which they are incorporated, are not realized with the use of existing suspension travel control technologies.

Limiting suspension system travel in the longitudinal direction and providing redundancy for longitudinal control, such as for example, in the event of the loss of a linkage, is also desired.

The present disclosure addresses the needs and/or shortcomings of prior art suspension systems

SUMMARY OF THE INVENTION

There are several aspects of the present subject matter which may be embodied separately or together in the devices and systems described and claimed herein. These aspects may be employed alone or in combination with other aspects of the subject matter, and the description of these aspects together is not intended to preclude the use of these aspects separately or the claiming of such aspects separately as set forth in the claims appended hereto.

In one aspect of this disclosure, a suspension travel control system for a vehicle is disclosed that includes a vehicle frame, a stop post, a suspension travel control formation and a vehicle suspension system. The stop post is secured at one end to the vehicle frame and presents at least one contact surface on its exterior surface. The suspension travel control formation has a body and a base: the body has an interior surface that defines an interior space. The vehicle suspension system includes an axle and a main support member movably connected to the vehicle frame to permit the main support member to move at least in part in a vertical direction. The suspension travel control formation, the main support member and the axle are coupled by an axle coupling assembly. The stop post is positioned in the interior space of the body of the suspension travel control formation for the engagement of the at least one contact surface with the interior surface of the body to limit downward travel of the main support member or the axle relative to the vehicle frame.

In another aspect of this disclosure, a suspension travel control system for a vehicle is disclosed that includes a vehicle frame, a stop post, a suspension travel control formation and a vehicle suspension system. The stop post is secured at one end to the vehicle frame and presents a first contact surface on its exterior surface. The suspension travel control formation has a body and a base and presents an interior surface that defines an interior space. The vehicle suspension system includes an axle and a main support member movably connected to the vehicle frame at a first end portion to permit the main support member to move at least in part in a vertical direction. The suspension travel control formation, the main support member and the axle are fixed in relation one another by one or more fasteners and undergo generally vertical movement between a first position or jounce position, and a second position or rebound position. The stop post is positioned in the interior space of the body of the suspension travel control formation for the engagement of the first contact surface of the stop post with a first portion of the interior surface of the suspension travel control formation to limit travel of the axle or the suspension linkage in a first direction that is not parallel to the generally vertical movement of the axle.

In yet another aspect of the invention a suspension travel control system for a vehicle is disclosed that includes a vehicle frame, a stop post, a suspension travel control formation and a vehicle suspension system. The stop post is secured at one end to the vehicle frame and presents a first surface and a second surface. The suspension travel control formation has a body and a base and presents a first contact surface and a second contact surface, the first contact surface spaced apart from and on opposite sides of the stop post from the second contact surface. The vehicle suspension system includes an axle, a suspension linkage that is longitudinally disposed and movably connected to the vehicle frame. The axle, the suspension linkage and the suspension travel control formation are fixed in relation to one another by one or more fasteners. The suspension travel control formation and stop post are configured to move relative to one another and in accordance with the movement of the suspension system during operation. The first surface of the stop post and the first contact surface of the suspension travel control formation are positioned for engagement with one another to limit movement of the suspension system in a first direction, and the second surface of the stop post and the second contact surface of the suspension travel control formation are positioned for engagement with one another to limit movement of the suspension system in a second direction, and the first direction and the second direction are generally opposite one another.

BRIEF DESCRIPTION OF THE DRAWINGS

In describing the preferred examples, reference is made to the accompanying drawing figures.

FIG. 1A is left side, upper rear perspective view of a portion of a vehicle suspension system incorporating a suspension travel control system in rebound position according to a first embodiment of the present disclosure.

FIG. 1B is a side elevational view of the subject matter of FIG. 1A.

FIG. 1C is a top plan view of the embodiment shown in FIGS. 1A-1B.

FIG. 2A is left side, upper rear perspective view of a portion of a vehicle suspension system incorporating a suspension travel control system in jounce position according to a first embodiment of the present disclosure.

FIG. 2B is a side elevational view of the subject matter of FIG. 2A.

FIG. 2C is a top plan view of the embodiment shown in FIGS. 2A-2B.

FIG. 3A is left side, upper rear perspective view of the subject matter of FIG. 1A-2C with a further modification of the present disclosure.

FIG. 3B is a side elevational view of the subject matter of FIG. 3A.

FIG. 3C is a top plan view of the embodiment shown in FIGS. 3A-3B.

FIG. 4A is a front left side perspective view of a vehicle suspension system without wheel ends incorporating the suspension travel control system of FIGS. 1A-2C in a neutral state.

FIG. 4B is a side elevational view of the subject matter shown in FIG. 4A.

FIG. 4C is an exploded, upper perspective view that includes the component shown in FIGS. 4A-4B and its mirror image component.

FIG. 4D is a non-exploded, upper perspective view of a suspension travel control formation of the embodiment shown in FIGS. 1A-4B.

FIG. 4E is an upper perspective of the top mounting pad of the embodiment shown in FIGS. 1A-4B.

FIG. 4F is an enlarged, left side elevational view of select components of the embodiment shown in FIGS. 1A-4B with the top mounting pad of the axle coupling assembly in phantom.

FIG. 5A is a suspension travel control formation of a second embodiment of the present disclosure.

FIG. 5B is a left side, upper rear perspective view of selected components of a vehicle suspension incorporating a suspension travel control system according to a second embodiment of the present disclosure

FIG. 5C is cross sectional side view of the subject matter shown in FIG. 5B taken through the centerbolt along a vertical plane parallel to the main support member.

FIG. 5D is an exploded, left side, lower front perspective view of the subject matter of FIG. 5B.

FIG. 6A is left side, upper rear perspective view of a portion of a vehicle suspension system incorporating a suspension travel control system in rebound position according to a third embodiment of the present disclosure.

FIG. 6B is a left side, upper front perspective view of a select component of the embodiment shown in FIG. 6A.

FIG. 6C is a side elevational view of the select component shown in FIG. 6B.

FIG. 6D is a top perspective view of the select component shown in FIGS. 6B-6C.

FIG. 6E is a front end view of the select component shown in FIGS. 6B-6D.

FIG. 7 is left side, upper rear perspective view of a portion of a vehicle suspension system incorporating a suspension travel control system in a neutral state according to a fourth embodiment of the present disclosure.

FIG. 8 is left side elevational view of a portion of a vehicle suspension system incorporating a suspension travel control system in rebound position according to a fifth embodiment of the present disclosure.

FIG. 9 is a left side, upper rear perspective view of a portion of a vehicle suspension system incorporating a suspension travel control system in jounce position according to a sixth embodiment of the present disclosure.

FIG. 10A is a left side, upper rear perspective view of a portion of a vehicle suspension system incorporating a suspension travel control system in a neutral state according to a seventh embodiment of the present disclosure.

FIG. 10B is a left side, upper rear perspective view of a portion of a vehicle suspension system incorporating a suspension travel control system in a neutral state according to a variation of a seventh embodiment of the present disclosure.

FIG. 11 is a left side elevational view of a multilink suspension having non-parallel upper and lower control arms and incorporating a suspension travel control system of the present disclosure.

FIG. 12 is left side elevational view of a four bag suspension system incorporating a suspension travel control system of the present disclosure.

DETAILED DESCRIPTION

The embodiments disclosed herein are for the purpose of providing a description of the present subject matter, and it is understood that the subject matter may be embodied in various other forms and combinations not shown in detail. Therefore, specific designs and features disclosed herein are not to be interpreted as limiting the subject matter as defined in the accompanying claims.

A suspension system incorporating a first example suspension travel control system of the present disclosure is indicated in general at 10 (FIGS. 4A & 4B). FIGS. 4A and 4B has the wheel ends and brakes removed to more clearly see the components that will be referred to or discussed herein. Turning to FIGS. 4A and 4B, a suspension system 10 is illustrated for coupling a longitudinally extending frame member 12 on one side of a vehicle chassis to a laterally extending axle 14 that is disposed below the frame member 12. As with the other drawings in this disclosure, it will be appreciated that the figures show a system for one side of a wheeled vehicle or trailer and a similar system would be provided on the opposite side to form a full suspension system.

The first example suspension system 10 includes at least one longitudinally oriented, suspension linkage, which in this example is in the form of a generally Z-shaped or gooseneck leaf spring also referred to as a main support member 16, It will be appreciated that the longitudinally oriented, suspension linkage may be any suitable, elongated single leaf spring, multileaf spring, beam spring, leading/trailing arm, rigid suspension beam, control arm or other elongated spring or beam element that is secured or connected, directly or indirectly, such as via a bushing assembly, to the vehicle frame or subframe or hanger bracket, at one end or end portion of the suspension linkage and at another end or end portion of the suspension linkage is secured or connected, directly or indirectly, such as via an air spring or bushing assembly, to the vehicle frame or subframe, or hanger bracket.

The suspension linkage, which is a main support member 16 in the first example suspension system shown in FIG. 4A, extends over the axle 14 in an overslung arrangement. In other suspension systems, the suspension linkage may extend over, under, through or around the axle, without departing from the scope of the present disclosure. The axle 14 is connected to the main support member 16 through the use of an axle coupling assembly, which in this example, rigidly secures the axle 14 to the suspension linkage 16 in the manner discussed below. The main support member 16 also is movably connected to the vehicle frame to permit the suspension linkage 16 and axle 14 to move up and down with the suspension system during use. In this example, the main support member 16 has a first end that includes a cylindrical eye portion 9 pivotally connected to the frame hanger bracket 8 with materials and techniques known to those skilled in the art, which may include for example, the use of a bushing and pivot bolt as appropriate. In this example, the axle 14 and the main support member 16 pivot about a rotational axis. During normal use, the travel path or movement of the axle 14 and the main support member 16 generally follows an arc defined in substantial part by the main support member's pivotal connection to the vehicle frame via bracket 8.

An air spring 2 is attached at its upper side to an air spring bracket 4 mounted to the frame member 12. At its lower side, air spring 2 is seated on a cross channel 6 positioned on the distal end of the main support member 16. A shock absorber (not shown) also may be included and be pivotally connected at its upper end to a bracket mounted on the vehicle frame member 12 and attached at its bottom end to a lower shock bracket positioned on the trailing end of the main support member 16. Although the suspension system incorporating the first example suspension travel control system, as illustrated in FIGS. 4A and 4B, employs an air spring, it is not limited to such a configuration, and may be deployed with other suspension types, such for example, the suspension type illustrated in U.S. Pat. No. 9,050,873 which employs a straight monoleaf spring design with shock absorber, with and without an air spring, as well as other suspension types referred to or disclosed herein without departing from the scope of the present disclosure.

As shown in FIGS. 4A and 4B, an axle coupling assembly 18 operatively couples the axle 14 to the main support member 16. From the top downward beginning with the top mounting pad, the axle coupling assembly 18 includes a top mounting pad or first mounting pad 20, also known as a first guide plate or clamp plate; a suspension travel control formation 46 which will be discussed in further detail below, an optional caster wedge 22 disposed between the main support member 16 and the axle 14; and a bottom mounting paid or second mounting pad 24, also known as a second guide plate or clamp plate. A pair of U-shaped fastener assemblies 26,28, which in the first example embodiment are shown as first and second U bolts and connectors are used to clamp together the aforementioned components in fixed relation to another.

The suspension travel control system includes the suspension travel control formation 46 referred to above and a stop member or stop post 34, which is discussed later herein. The suspension travel control formation 46 has a body 48 and a base 42. The body 48 provides an interior surface defining an interior space 47. The base 42 extends in the longitudinal, lateral and vertical directions and supports the body 48, as further discussed herein. The first example suspension travel control formation may be integrally formed in one piece construction, or provided as an assembly, such as, for example, as shown in FIGS. 4C, 4D, and 4G in which mirror image, inboard and outboard elements 46A, 46B interface along a centrally positioned, longitudinal, vertical plane and are then secured together by suitable means, such as for example, by welding.

In this first example embodiment, the body 48 of the suspension travel control formation 46 is a rigid structure and includes a first frame member or first portion 62, a second frame member or second portion 68, and a third frame member or third portion 74 (FIG. 4D), which together provide an interior surface defining an elongated interior space or slot 47. Each of the first, second and third frame members 62,68,74 have a first longitudinal end portion and a second longitudinal end portion. The first frame member 62 and third frame member 74 are spaced apart and extend generally vertically from a first longitudinal end portion that is connected to or transitions from a separate shoulder portion 56, 80 of the base 42. The shape and the orientation of the first frame member and the third frame member follow a path that is generally consistent with or generally parallel to the path or direction of travel of the axle 14 and the main support member 16 and during normal or ordinary operating conditions. In this first example, this path generally follows an arc, the shape and orientation of which may be determined in substantial part by its radius, or distance to the axis of rotation, which in the first example, is generally perpendicular to and extends through the eye of the main support member. The spacing between the first frame member and the third frame member are sufficient to accommodate flexing of the main support member and other suspension compliance features that alter or vary this distance during normal or ordinary use. The second longitudinal end portions of the first frame member 62 and third frame member 74 connect or transition into respectively, the first and second longitudinal end portions the second frame member 68 located at the top end portion of the elongated space 47, which is C- or U-shaped in the first example suspension travel control formation but which may be varied without department from the scope of the present disclosure.

A stop member which in the first example is a stop post 34 is positioned in the interior space 47 of the body 48 of the suspension travel control formation 46 in a manner that permits the stop post and body to move in relation to one another during use. The stop post 34 has a first end portion and a second end portion, an exterior surface which in the first example extends in the axial and radial directions, and a central axis that is generally transverse to the orientation of the body 48 of the suspension travel control formation 46. The stop post 34 is secured at its first end to the vehicle frame member 12 by bracket 33 (FIG. 4A). Alternatively, the first end of the stop post 34 may extend into and through the vehicle frame member 12 and be secured by a bracket positioned on the inboard side of the vehicle frame. The stop post 34 presents a contact surface at different locations of its exterior surface, including on the top exterior surface 38 facing the interior surface of the second frame member 68 of the body, on the bottom exterior surface 36 facing the top surface of the mounting pad 20, and on the exterior surfaces fore and aft (35 and 37) facing the interior surfaces of the respective first and third frame members 62, 74. Each stop surface or contact surface of the stop post 34 is positioned and configured for engagement with a corresponding interior surface of the first frame member 62, second frame member 68 or third frame member 74 or top mounting pad 20 to control and/or to limit travel of the suspension in a given direction as further discussed herein.

An optional flange 31 presenting an inboard facing surface 32 can be connected to the second end portion of the stop post 34 to provide a barrier against excessive lateral movement that would laterally separate the body 48 of the suspension travel control formation 46 from the stop post 34 thereby exiting the stop post from the interior space 47 of the body 48 of the suspension travel control formation 46 (FIGS. 3A-3C). In position, the span of the flange will preferably exceed the distance by which the first frame member 62 and third frame member 74 of the body 48 are separated. While the shape of the example flange 31 in FIGS. 3A-3B is generally circular, it may be varied without departing from the scope of the present disclosure. The flange 31 may be secured at the second end portion of the stop post 34 by either internal or external threads that are received within respectively, complementary external or internal threading in the centered hub of the flange or by other fastening techniques and materials known to those skilled in the art.

The base 42 of the suspension travel control formation 46 is provided in the first example embodiment by the opposing, outwardly extending, inboard and outboard flanges 44A, 44B (FIG. 4D) which turn upward to converge or interface along a centrally positioned, longitudinal, vertical plane, to provide spaced apart, vertically and longitudinally oriented, first and second shoulder portions 56,80, each having an interior end portion or proximal end portion and an exterior end or distal end portion. The vertically oriented, shoulder portions 56,80 positioned outside the first longitudinal end portions of the first frame member 62 and third frame member 74 reinforces the strength of the suspension travel control formation. The distal end portion of each shoulder portion 56, 58 is further extended by its connection or transition to an upwardly extending, longitudinally oriented flange 50,88, an end portion of which is configured to contact a corresponding end face 19,21 of the top mounting pad 20. This feature assists in securing the suspension travel control formation 46 in place and in more evenly distributing operational loads and stresses throughout the suspension travel control formation 46 and top mounting pad 20.

The top surface of the top mounting pad 20 has fastener engagement surfaces 23,25 which in this first example embodiment, are two upwardly facing grooved surfaces, each designed to receive a bight portion of a U shaped fastener 26,28. The top surface of the top mounting pad 20 between the fastener engagement surfaces 23,25 provides a contact surface 17 in the form of a depression or recess, which during vehicle operation, is intermittently brought into contact with a stop surface or contact surface 36 positioned on the bottom exterior surface of the stop post 34 to limit upward jounce travel or other lifting of the main support member, the axle and/or the suspension system (FIGS. 2A-2C) relative to the vehicle frame. In the example shown in FIGS. 2A-2C, this contact surface 36 of stop post 34 is represented by the flattened portion on the bottom exterior surface of the stop post 34, but may be differently configured without departing from the scope of the present disclosure. The creation of the recess that presents the contact surface 17 on the top surface of the top mounting pad 20 reduces its weight and also permits a greater range of travel of the main support member 16 to the jounce position within the packaging constraints of the suspension system.

An opening in the bottom surface of the base 42 defines a cavity 15 in which the first example suspension travel control formation is received. (FIG. 4E). The cavity 15 extends vertically through the mounting pad 20 exiting the top surface between the U shaped fastener engagement surfaces 23,25 and stopping short of the top surface between the U shaped fastener engagement surfaces 23,25 and the end faces 19,21 of the top mounting pad 20 (FIG. 4E). When the suspension travel control formation 46 is received within the top mounting pad 20 and this combination is mounted on the main support member 16, the bottom surface of the top mounting pad 20, the interior wall of the cavity 15 of the top mounting pad 20, and the top surface of the main support member 16 secure the suspension travel control formation 46 in place. In this arrangement, the interior wall of the cavity 15 contacts the top surface of the outwardly extending flanges 44A,44B (FIG. 4F), the lateral surfaces and top edge of the shoulder portions 56,58 of the base 42 and the lateral surfaces and exterior edge of the first frame member 62 and third frame member 74 of the body 48 of the suspension travel control formation 46.

Travel of the suspension system 10, including the suspension travel control formation 46, the axle 14 and the main support member 16, is desirably controlled and/or limited by the use of the suspension travel control system of the present disclosure.

During rebound travel of the suspension system 10, the axle 14, the main support member 16 and the suspension travel control formation 46 travel downward generally along a path determined by the design of the suspension system. In this first example, this path generally follows an arc determined by the main support member's pivotal connection with the vehicle frame. As this occurs, the body 48 of the suspension travel control formation 46 travels downward along this arc about the stop post 34 until the contact surface 38 on the top exterior surface of the stop post 34 is engaged by the interior surface of the second frame member 68, limiting further downward travel of the suspension travel control formation 46, the main support member 16 and the axle 14 relative to the vehicle frame. It is preferable during normal or ordinary operating conditions that the interior surfaces of the first frame member 62 and the third frame member 74 avoid or minimize sustained contact with the exterior surface of the stop post 34 during downward rebound travel of the suspension system.

The suspension travel control system of the present disclosure may also be configured to provide longitudinal redundancy in one or more directions as discussed below. In the event of the failure of a suspension linkage or component, the axle 14, the main support member 16 and/or the suspension travel control formation 46 may shift in a direction that is generally perpendicular to or nonparallel to or askew of the path or direction of travel of the axle 14 and the main support member 16 during normal or ordinary operating conditions. In the event of such a failure, generally radially inward or forward translational movement of the axle 14 or the main support member 16 will be limited by the engagement of the interior surface of the third frame member 74 with the opposing contact surface 37 on the exterior surface of the stop post 34. Generally radially outward or rearward translational movement of the axle 14 or the main support member 16 will be limited by the engagement of the interior surface of the first frame member 62 and the opposing contact surface 35 on the exterior surface of the stop post 34.

It will be appreciated that the size, shape and orientation of the suspension travel control formation may vary in accordance with the design and travel path of the suspension system without departing from the scope of the present disclosure. As one example shown in FIG. 11, a 4 bar linkage suspension, as referred to in the art, includes non-parallel suspension linkages in the form of non-parallel upper and lower control arms (714,715) resulting in a configuration where a theoretical extension of these linkages identifies a virtual center of rotation (designated as “VC” in FIG. 11) or axis of rotation where the extended centerlines of the control arms intersect, at a location that is spaced apart from and on the opposite side of the hanger bracket from the axle. The upper control arm 714 is pivotally connected at one end to a frame hanger 708 and at another end to a top mounting pad 720 of the axle coupling assembly. The lower control arm 715 is pivotally connected at one end to the frame hanger 708 and at another end to a bottom mounting pad 724 which also provides a seat or mount for an air spring 2 and a shock absorber 3, each of which are connected at their respective upper ends to the vehicle frame. It will be appreciated that as the axle 14 undergoes movement during normal or ordinary operating conditions, generally in a vertical direction, the intersection of the extended centerlines of the control arms and thus the virtual center of rotation of the suspension system will also move. As the distance between the virtual center and the axle decreases over the range of motion of the suspension system, the travel path of the axle may bend more sharply towards the virtual center. As the distance between the virtual center and the axle travel path increases, the travel path of the axle may bend further away from the virtual center. Additionally, the base of the suspension travel control formation 746 resembles a wedge to accommodate the angled orientation of the axle. The size, shape and orientation of the suspension travel control formation can be varied or customized to different suspension types without departing from the scope of the present disclosure. The suspension system of FIG. 11 is shown and described in U.S. Pat. No. 9,085,212, the entirety of which is incorporated herein by reference.

The suspension system of FIG. 12 is a four air bag suspension appropriate for coaches and passenger buses among other types of vehicles and is similar to that shown and described in U.S. Publication No. 2016/0280026A 1, the entirety of which is incorporated herein by reference. Suspension linkages in the form of an upper control arm 814 pivotally connected at one end to the vehicle frame 12 and at the other end to the axle 14 and a lower control arm 815 pivotally connected at one end to the lower portion of a frame hanger 808 and at another end to another suspension linkage in the form of a suspension beam 817. An air spring 2 is positioned between each of the forward and rearward end portions of the suspension beam 817. The suspension travel control formation 846 of the suspension system of FIG. 12 is in the shape of an arc that bends to the right in accordance with the travel path or movement of the axle during normal or ordinary operation of this suspension system.

The second through sixth example suspension travel control systems, for purposes of illustration and facilitating discussion, are shown as being deployed on the same type of suspension system as shown in FIGS. 4A and 4B. Accordingly, the same reference numerals and descriptions above with respect to the first example apply as to those same components. Except as described or as noted below, the example suspension travel control systems discussed below feature functionality and construction that is similar to those described in the embodiment of FIGS. 4A and 4B. It will be appreciated that each of the example suspension travel control systems are not limited to the particular suspension system in which they are illustrated and may be deployed a variety of suspension systems without department from the scope of the present disclosure.

A suspension travel control formation for a second example suspension travel control system is indicated in general at 146.

The second example, suspension travel control formation 146 has a body 148 and a base 142 (FIG. 5A). The body 148 provides an interior surface defining an interior space or slot 147.

In this second example, the body 148 is positioned on the inboard side of the suspension travel control formation 146. The inboard side of the body 148 may be generally flush with inboard lateral edge of the main support member 16. The body 148 includes a first frame member or first portion 162, a second frame member or second portion 168, and a third frame member or third portion 174, which together provide the interior surface defining an elongated interior space 147. (FIGS. 5A-5C). The first, second and third frame members 162, 168, 174 each have first and second longitudinal end portions. The first and third frame members 162, 174 are spaced apart and extend vertically from their respective first longitudinal end portions which are connected to or transition from a shoulder portion 156 to follow an arc that is generally consistent with the arc of rotation of the main support member 16 about its pivotal connection with the vehicle frame. The second longitudinal end portions of the respective first frame member 162 and third frame member 174 connect or transition into respectively, first and second longitudinal end portions of the C- or U-shaped second frame member 168 located at the top end portion of the elongated space 147.

As shown in FIG. 5A, the base 142 of the suspension travel control formation 146 supports the body 148 and extends in the longitudinal and lateral directions and is positioned between the bottom surface of the top mounting pad 120 and the top surface of the main support member 16. The base 142 connects or transitions into the body 148 via shoulder portion 156 on the inboard side of the base 142. Fore and aft of the shoulder portion are, respectively, first and second grooves 113,115 which improve component fit and joint integrity of the assembly shown in FIGS. 5c and 5 d.

A depression or recess in the top surface of the top mounting pad 120 between the fastener engagement surfaces 123,125 presents a contact surface 117, which during vehicle operation, is intermittently brought into contact with a stop surface or contact surface positioned on the bottom exterior surface of the stop post to limit upward jounce travel or other lifting of the main support member, the axle and/or the suspension system. The creation of the recess that presents contact surface 117 on the top surface of the top mounting pad 120 reduces its weight and also permits a greater range of travel of the main support member 16 to the jounce position within the packaging constraints of the suspension system.

The main support member 16, which in this example is a longitudinally oriented, generally Z-shaped leaf spring, also includes a locator 106, shown for example in the form of a passageway 106, 105, 104 that extends in alignment through the main support member 16, the base 142 of the suspension travel control formation 16 and the top mounting pad 120. In this example, the passageway receives a throughbolt 101 or externally threaded fastener that is secured in place by a nut or connector 103, positioned in counterbore 121 in the top mounting pad 120. Preferably, the counterbore is of sufficient depth to place the fastener assembly below surface 117 to avoid direct contact between the fastener assembly and the contact surface of the stop post when the suspension is in the jounce position. It will be appreciated that the locator and fastener assembly of the type shown in FIGS. 5B through 5D help to position and hold the main support member 16, the suspension travel control formation 146 and the top mounting pad 120 together, in proper longitudinal and lateral relation to one another and within the axle coupling assembly in which they will eventually be incorporated. This feature also permits the main support member 16, the suspension travel control formation 146 and the top mounting pad 120 to be shipped in assembled form, minimizing the number of parts that need to be separately handled and inventoried in downstream production of a suspension system or wheeled vehicle.

As shown in FIGS. 6A-6E, a third example, suspension travel control formation 246 has a body 248 and a base 242 which are integrated with the top mounting pad in a single, one piece construction.

As in the first example, the body 248 of the suspension travel control formation 246 includes a first frame member or first portion 262, a second frame member or second portion 268, and a third frame member or third portion 274, which together provide the interior surface defining an elongated interior space 247. The first, second and third frame members 262, 268, 274 each have first and second longitudinal end portions. The first frame member 262 and the third frame member 274 are spaced apart. The first and third frame members 262, 274 extend vertically from their respective first longitudinal end portions which are connected to or transition from respectively, separate shoulder portions 256, 280 to follow a path that is generally consistent with or parallel to the path or direction of travel of the main support member and axle during normal or ordinary operating conditions, which in this example, is an arc that is generally consistent with or parallel to the an arc defined by the pivotal rotation of the main support member 16 about its rotational axis. The second longitudinal end portions of the respective first frame member 262 and third frame member 264 connect or transition into respectively, first and second longitudinal end portions of the C- or U-shaped second frame member 268 located at the top end portion of the elongated space 247.

The base 242 incorporates a top mounting pad which has U shaped fastener engagement surfaces 223, 225 for receiving U shaped fastener assemblies 26,28 which clamp together the components of the axle coupling assembly in fixed relation to one another. The base 242 connects or transitions into the body 248 via shoulder portions 256, 280. A depression or recess in the top surface of the top mounting pad 220 between the fastener engagement surfaces 223,225 presents a surface 217, which during vehicle operation, is intermittently brought into contact with a stop surface or contact surface 36 positioned on the bottom exterior surface of the stop post 34 to limit upward jounce travel or other lifting of the main support member 16, the axle and/or the suspension system. The creation of the recess that presents surface 217 on the top surface of the top mounting pad 220 reduces its weight and also permits a greater range of travel of the main support member 16 to the jounce position within the packaging constraints of the suspension system.

The third example suspension travel control formation 246 is preferably cast as an integrally formed, one piece structure, however, it may also be manufactured using any other suitable method and material, as a single or multi-piece structure.

As shown in FIG. 7, a fourth example suspension travel control formation 346 has a body 348 and a base 342.

As in the first example, the body 348 of the suspension travel control formation 146 includes a first frame member or first portion 362, a second frame member or second portion 368, and a third frame member or third portion 374, which together provide the interior surface defining an elongated interior space 347. The first, second and third frame members 362, 368, 374 each have first and second longitudinal end portions. The first frame member 362 and third frame member 374 are spaced apart and extend vertically from a respective first longitudinal end portion that is connected to or transitions from a separate shoulder portion 356, 380 to follow an arc that is generally consistent with the arc of rotation of the main support member 16 about its pivotal connection with the vehicle frame 12. The second longitudinal end portions of the respective first frame member 362 and third frame member 364 connect or transition into respectively, first and second longitudinal end portions of the C- or U-shaped second frame member 368 located at the top end portion of the elongated space 347.

The base 342 of this fourth example resembles a clamp like structure and includes a first plate 341 and a second plate 343A,343B which are connected by a vertical wall 340. The first plate 341 is horizontally disposed between the axle 14 and the main support member 16. A caster wedge 22 is also present between the axle 14 and the main support member 16. In the transition from the vertical wall 340 to the second plate 343A,343B, the second plate presents two, spaced apart sections 343A,343B which overlay the top mounting pad and are fixedly secured thereto by fasteners that extend though each section of the second plate 343A, 343B into the top mounting pad. The exposed portion of the top surface 317 of the top mounting pad 320 provides a direct contact surface for engagement with the bottom exterior surface 36 of the stop post 34 to limit upward jounce travel of the main support member 16, axle 14 and suspension travel control formation 346. First and second U shaped U shaped assemblies 26,28 received within respective engagement surface 23,25 of the top mounting pad clamp together the components of the axle coupling assembly.

The fourth example suspension travel control formation 346 is preferably fabricated from steel plate material, however, it may also be manufactured using any other suitable method and material, as a single or multi-piece structure.

The fifth and sixth example suspension travel control formations 446 show different techniques for positioning and securing the body 448,548 of the suspension travel control formation 446,546 closer to the pivotal connection of the first end of the main support member 16. In each instance, the body 448,548 is positioned above a location along the length of the main support member 16 between the axle 14 and the first end of the main support member 16. It will be appreciated that moving the body 448,548 of the suspension travel control formation 446,546 closer to the axis of rotation of the main support member 16 reduces the amount of vertical displacement which the body of the suspension travel control formation 446,546 must accommodate in a given suspension system, and accordingly its vertical size.

In the fifth example, the body 448 of the suspension travel control formation 446 has an elongated interior space 447 defined by an interior surface or interior edge having a first side or first portion 462, a second side or second portion 468, a third side or third portion 474, and a fourth side or fourth portion 476. In this example, the body 448 itself encloses the interior space 447. The first side portion 462 and third side portion 474 are spaced apart and extend vertically from their connection with the fourth side or fourth portion 476 positioned at the bottom of the interior space 447. The first side portion 462 and third side portion 474 also connect or transition into the second side portion 468, located at the top of the interior space 447. The fourth side portion 476 is positioned and configured for engagement with contact surface 36 on the bottom exterior surface of the stop post 34 to limit upward jounce travel of the suspension system.

The body 448 is connected proximate its third side portion 474 to a generally vertical member 443 of an L shaped base 442, the horizontal member 441 of which is positioned between the main support member 16 and top mounting pad 320. A support bracket 427 having a first flange attached to the top of the mounting pad and a second flange attached to the vertical member 443 of the L-shaped base on the side opposite the body 448 reinforces the strength and positioning of the body relative to the base 442. The body 448 and the base 442 can be formed from the same piece of steel, or alternatively, the body can also be a separate piece that presents an outboard flange for attachment to the vertical member 443 of the L-shaped base using the same fasteners as are used for the second flange of the support bracket. A body 448 that is separately formed from the base 442 and removably secured thereto with threaded fasteners or other suitable fastening techniques as last described permits the body 448 to be installed, serviced or replaced without disassembling the axle coupling assembly.

In the sixth example suspension control formation 546, the body 548 of the suspension travel control formation 546 is supported by the base 542 positioned in a manner similar to that of a braced cantilever and without requiring an additional support bracket similar to that shown in FIG. 8.

In the sixth example, the body 548 of the suspension travel control formation 546 includes a first frame member or first portion 562, a second frame member or second portion 568, and a third frame member or third portion 574, each having a first longitudinal end portion and a second longitudinal end portion. The first frame member 562 and third frame member 574 are spaced apart. Each extends vertically from the first longitudinal end portion which is connected to or transitions from a second portion of the base 542 positioned outside of the U shaped fastener assembly to follow an arc that is generally consistent with the arc of rotation of the main support member 16 about its pivotal connection with the vehicle frame 12. The second longitudinal end portion of the first frame member 562 and the third frame member 574 connect or transition into respectively, the first and second longitudinal end portions of the C-or U-shaped second frame member 568 located at the top end portion of the elongated interior space 547.

The base 542 has a first portion 541 and second portion 543. The former extends in the longitudinal and lateral directions and is positioned between the main support member 16 and the top mounting pad 20. The first portion 541 of the base 542 transitions into the second portion 543 referred to above which is elevated and longitudinally offset from the first position 541 in the direction of the axis of rotation of the main support member 16. A wedge or wedge portion 550 helps support the second portion 543 of the base 542 and the body 548 in their respective positions.

The seventh example embodiment incorporates the suspension travel control system into a vehicle suspension in a different manner than previously depicted.

FIGS. 10A and 10B show a traditional trailing arm suspension known to those skilled in the art and includes left and right side, pivotally mounted, trailing arms (beams) 616. An axle 614 extends through the trailing arms 616 on both sides of the suspension. An air spring 2 is attached at one end to the distal end of the beam and at another end to the bracket 4 connected to the vehicle frame member 612.

A suspension travel control system of the present disclosure as incorporated in this seventh example includes a stop post 34 connected directly to the vehicle frame member 12 and a suspension travel control formation 646 which includes a body 648 and a base 642.

The body 648 has an interior surface defining an interior space 647. The body of the suspension travel control formation includes a first frame member or first portion 662, a second frame member or second portion 668, and a third frame member or third portion 674, each having a first longitudinal end portion and a second longitudinal end portion. The first frame member 662 and third frame member 674 are spaced apart 642. Each extends vertically from its first longitudinal end portion which is connected to or transitions from the base 642 to follow an arc that is generally consistent with the arc of rotation of the suspension linkage, which in this example, is a leading arm/trailing arm 616, about its pivotal connection with the vehicle frame. The second longitudinal end portions of the first frame member 662 and the third frame member 674 connect or transition into respectively, the first and second longitudinal end portions of the C- or U-shaped second frame member 668 located at the top end portion of the elongated interior space 647.

The base 642 of the suspension travel control formation 646 is welded but may also be connected by other suitable means to the top surface of the leading arm/trailing arm 616 in FIG. 10A and to the inboard side of the leading arm/trailing arm 616 in FIG. 10B.

It will be understood that the embodiments described above are illustrative of some of the applications of the principles of the present subject matter. Numerous modifications may be made by those skilled in the art without departing from the spirit and scope of the claimed subject matter, including combinations of features that are individually disclosed or claimed herein. For these reasons, the scope of this disclosure is not limited to the above description but is as set forth in the following claims, and it is understood that claims may be directed to the features hereof, including as combinations of features that are individually disclosed or claimed herein. 

1. A suspension travel control system for a vehicle, comprising, a vehicle frame, a stop post secured at one end to the vehicle frame and presenting at least one contact surface, a vehicle suspension system comprising, an axle, a suspension linkage, said suspension linkage being longitudinally disposed and movably connected to the vehicle frame, a suspension travel control formation having a body and a base, the body having an interior surface defining an interior space, wherein the axle, the suspension linkage and the suspension travel control formation are coupled by an axle coupling assembly in a manner that permits the axle, the suspension linkage and the suspension travel control formation to move at least in part in a vertical direction, and wherein the stop post is positioned in the interior space for the engagement of the at least one contact surface of the stop post with the interior surface of the body of the suspension travel control formation to limit downward travel of the axle or the suspension linkage.
 2. The suspension travel control system of claim 1 wherein the interior space of the suspension travel control formation is elongated.
 3. The suspension travel control system of claim 1 wherein a portion of the interior surface of the suspension travel control formation is C shaped or U shaped.
 4. The suspension travel control system of claim 1 wherein the body and the base of the suspension travel control formation form a closed loop.
 5. The suspension travel control system of claim 1 wherein the suspension linkage includes a main support member,
 6. The suspension travel control system of claim 1 wherein the body of the suspension travel control formation is in the shape of an upside down U having a first leg and a second leg, the first leg and the second leg being of unequal length.
 7. The suspension travel control system of claim 1, wherein the body of the suspension travel control formation includes a first frame member, a second frame member and a third frame member providing the interior surface defining the interior space.
 8. The suspension travel control system of claim 7, the first frame member, the second frame member and the third frame member each having a first longitudinal end portion and a second longitudinal end portion, the first frame member and the third frame member spaced apart, each extending generally vertically from their respective first longitudinal end portions which connect with or transition from the base, the respective second longitudinal end portions of the first frame member and the third frame member each connect with or transition from, respectively, the first and second longitudinal end portions of the second frame member, and the second frame member positioned at the top of the interior space.
 9. The suspension travel control system of claim 8, the suspension linkage movably connected to the vehicle frame at a first end of the suspension linkage to permit the suspension linkage to pivot about a rotational axis, the first frame member and the third frame member of the suspension travel control formation extending along a path that follows an arc about the rotational axis of the suspension linkage.
 10. The suspension travel control system of claim 7, the first frame member, the second frame member and the third frame member being integrally formed together.
 11. The suspension travel control system of claim 1, the stop post having a central axis and an exterior surface that extends in the axial direction and in the radial direction.
 12. The suspension travel control system of claim 7, the stop post having a contact surface positioned for engagement with the interior surface of the second frame member of the suspension travel control formation to limit downward rebound travel of the axle or the suspension linkage.
 13. The suspension travel control system of claim 7, the stop post having a contact surface positioned for engagement with the interior surface of the third frame member to limit movement of the axle or the suspension linkage in a forward direction generally perpendicular to a path defined by the movement of the stop post within the suspension travel control formation between a rebound and a jounce position.
 14. The suspension travel control system of claim 7, the stop post having a contact surface positioned for engagement with the interior surface of the first frame member to limit movement of the axle or the suspension linkage in a rearward direction generally perpendicular to a path defined by the movement of the stop post within the suspension travel control formation between a rebound and a jounce position.
 15. The suspension travel control system of claim 7 further comprising a flange mounted to the stop post, the suspension travel control formation disposed between the vehicle frame and the flange, the flange having an inboard facing contact surface positioned for engagement with the suspension travel control formation to limit outboard travel of the axle, the suspension linkage or the suspension travel control formation.
 16. The suspension travel control system of claim 1 further comprising a flange mounted to the stop post, the suspension travel control formation disposed between the vehicle frame and the flange, the flange having an inboard facing contact surface positioned for engagement with the suspension travel control formation to prevent lateral separation of the suspension travel control formation from the stop post during lateral movement of the suspension linkage or the axle in relation to the vehicle frame.
 17. The suspension travel control system of claim 15, the inboard facing contact surface of the flange being nonparallel or perpendicular to a central axis of the stop post.
 18. The suspension travel control system of claim 15, the inboard facing contact surface being longitudinally centered with respect to the central axis of the stop post.
 19. The suspension travel control system of claim 15, wherein the flange spans the distance between the first frame member and the third frame member of the body of the suspension travel control formation.
 20. The suspension travel control system of claim 1 wherein the suspension travel control formation resembles a fin.
 21. The suspension travel control system of claim 7, wherein the first and third members of the suspension travel control formation are generally parallel to one another.
 22. The suspension travel control system of claim 7, wherein the first and third frame members of the suspension travel control formation are arcuate in shape.
 23. The suspension travel control system of claim 1, the interior surface defining the interior space has a point of inflection.
 24. The suspension travel control system of claim 9, the body of the of the suspension control formation positioned above a location along the length of the suspension linkage and between the axle and the first end of the suspension linkage.
 25. The suspension travel control system of claim 1, the axle coupling assembly including a first mounting pad.
 26. The suspension travel control system of claim 25, the suspension travel control formation is integrally formed with the first mounting pad.
 27. The suspension travel control system of claim 25, the first mounting pad and the suspension travel control formation are discrete components.
 28. The suspension travel control system of claim 25, the first mounting pad and the suspension travel control formation are bolted together.
 29. The suspension travel control system of claim 25, the base of the suspension travel control formation disposed between the first mounting pad and the suspension linkage.
 30. The suspension travel control system of claim 1, the base of the suspension travel control formation disposed between the axle and the suspension linkage.
 31. The suspension travel control system of claim 1, the base of the suspension travel control formation disposed above and below the suspension linkage.
 32. The suspension travel control system of claim 28, the first mounting pad including a first end face and a second end face, the base of the suspension travel control formation having a first flange and a second flange, the base of the suspension travel control formation disposed between the first mounting pad and the suspension linkage, wherein the first flange and second flange of the base of the suspension travel control formation respectively engage the first end face and the second end face of the first mounting pad to limit movement of the suspension travel control formation relative to the first mounting pad.
 33. The suspension travel control system of claim 1, the axle coupling assembly including at least one fastener assembly.
 34. The suspension travel control system of claim of claim 33, the at least one fastener assembly having a U shape.
 35. The suspension travel control system of claim 1, wherein the suspension linkage is a leaf spring.
 36. The suspension travel control system of claim 35 wherein the leaf spring is a Z shape leaf spring.
 37. The suspension travel control system of claim 1 having an air spring positioned between the suspension linkage and the vehicle frame.
 38. A suspension travel control system for a vehicle, comprising, a vehicle frame, a stop post secured at one end to the vehicle frame and presenting a first contact surface, a vehicle suspension system comprising, an axle, a suspension linkage having a first end portion, the suspension linkage movably connected to the vehicle frame at the first end portion of the suspension linkage to permit the suspension linkage to move at least in part in a vertical direction, a suspension travel control formation having a body and a base and presenting an interior surface defining an interior space, wherein the axle, the suspension linkage, and the suspension travel control formation are fixed in relation to one another by one or more fasteners and undergo generally vertical movement between a first position or jounce position, and a second position or rebound position, wherein the stop post is positioned in the interior space for the engagement of the first contact surface with a first portion of the interior surface of the suspension travel control formation to limit travel of the axle or the suspension linkage in a first direction that is not parallel to the generally vertical movement of the axle.
 39. The suspension travel control system of claim 38 wherein the first direction is generally perpendicular to the generally vertical movement of the axle.
 40. The suspension travel control system of claim 39, the stop post having a second contact surface, the stop post positioned in the interior space for engagement of the second contact surface with a second portion of the interior surface of the body to limit travel of the axle or the suspension linkage in a second direction that is generally opposite the first direction and is not parallel to the generally vertical movement of the axle.
 41. A suspension travel control system for a vehicle, comprising, a vehicle frame, a stop post secured at one end to the vehicle frame and presenting a first surface and a second surface, a vehicle suspension system comprising, an axle, a suspension linkage, said suspension linkage being longitudinally disposed and movably connected to the vehicle frame, a suspension travel control formation having a body and a base and presenting a first contact surface and a second contact surface, the first contact surface spaced apart from, and on opposite sides of the stop post from the second contact surface, wherein the axle, the suspension linkage and the suspension travel control formation are fixed in relation to one another by one or more fasteners, and wherein the suspension travel control formation and stop post are configured to move relative to one another and in accordance with the movement of the suspension system during operation, and wherein the first surface of the stop post and the first contact surface of the suspension travel control formation are positioned for engagement with one another to limit movement of the suspension system in a first direction, and the second surface of the stop post and the second contact surface of the suspension travel control formation are positioned for engagement with one another to limit movement of the suspension system in a second direction, and the first direction and the second direction are generally opposite one another.
 42. The suspension travel control system of claim 41 wherein the first direction and the second direction are generally parallel to a longitudinal axis of the vehicle.
 43. The suspension travel control system of claim 41 wherein the first direction and the second direction are generally perpendicular to the longitudinal axis of the vehicle. 